Hazardous waste materials are frequently transported to disposal facilities in very large waste handling containers. A typical such container might measure 8'.times.18'.times.51 with an opening in the top thereof measuring 7'.times.14'. To safely close off this large opening, a one-piece lid must cover the entire opening and form a tight seal against the container body to prevent the hazardous materials from escaping during transport.
One example of such a lid is shown is U.S. Pat. No. 4,934,562 wherein the lid has a downwardly extending, longitudinal flange which rides along rollers positioned on top of the container. A complicated screw-type mechanism is used to raise the lid from a sealed position, and then the lid is slid laterally along the rollers roughly half its width until a pair of spring-biased hooks catch corresponding hinge bars at the edge of the top of the container. The lid is thus hingedly connected to the top of the container and is pivoted to the side and out of the way of the opening. In addition to the significant risk of failure of the screw mechanism to unseal and raise the lid and the difficulty of servicing the screw mechanism, the lid can easily be derailed from its tracks. Moreover, although fairly heavy, this lid has proven to be highly susceptible to the forces of a good wind gust which has picked the lid up, off and away from the container. It has also been found that the special spring-biased hooks do not reliably engage with the hinge members. This can and has left the lid skewed, derailed, and jammed. Another example of this type of sliding lid configuration is shown in U.S. Pat. No. 4,821,902. Here, the lid of a large waste container is supported for gliding horizontal movement atop rollers mounted to the top of the container.
What is needed is a simple and reliable mechanism for permitting the lid of a large hazardous waste handling container to be easily manipulated between a locked and sealed position to an open position clear of the corresponding opening.